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Living People Outnumber the Dead

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Foolishness. A meme going around claims the human population has swelled to the point that there are more people alive today than all those who have ever lived. But that's wrong; despite a quadrupling of the population in the past century, the number of people alive today is still dwarfed by the number of people who have died.

For most of history, human population grew slowly, if at all. From the time Homo habilis, the first more or less human, appeared two million years ago until they figured out how to grow their own food, Earth's population expanded to only about five million people and grew at less than .1% per year. It only reached 300 million by year 1 CE.

Then plagues killed off huge numbers of people, including 75 million wiped out by the "black death" in the 14th century alone. As a result, by 1650 the world population had only increased to about 500 million. By 1800, though, thanks to improved agriculture and sanitation, it doubled to more than one billion. Now Earth's population has exploded to over 6 billion.

Carl Haub, a demographer at the Population Reference Bureau figured out the number of people that have ever existed. He assumed two people, as we know them today, existed in 50,000 BCE (which is obviously not quite right because the numbers blur between humans and our ancestors such as Neadertals, but that close enough for this kind of estimate). Then, using historical growth rates and population benchmarks, he estimated that slightly over 106 billion people had ever been born.

So the 6 billion people alive today are only 6 percent of those that have ever lived.

Recently, the population has been increasing by about 1.2 percent each year, down from the late 1960s peak of a 2.1 percent. In fact, some countries, especially France and Japan, have very low birth rates and their populations are actually dwindling,

U.N.projections predicts that by 2050 the world's population will be around 9 billion and will stabilize at 10 billion sometime around 2200.

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